This application relates to a turbine airfoil, wherein a leading edge portion is formed of a material having a higher melt point than another portion of the airfoil.
Gas turbine engines are known and, typically, include a fan delivering air into a compressor. The air is compressed and delivered into a combustor section where it is mixed with fuel and ignited. Products of this combustion pass downstream over turbine rotors driving them to rotate.
The turbine rotors carry rotating blades having airfoils, and there are typically several stages of the rotating blades. There are also intermediate rows of vanes which are static and also include airfoils.
The blades and airfoils are subject to very high temperatures from the products of combustion. Designing the airfoils requires a good deal of trade-offs, in that, the airfoils are desirably lightweight, inexpensive and yet able to handle temperature and stress challenges. As an example, a leading edge of the airfoil is typically subject to much higher temperatures than the remainder of the airfoil body. Yet, airfoils have typically been formed of a single material. This has required additional cooling near the leading edge.
Typically, cooling is performed by routing cooling air through the airfoil. The additional cooling load while at the leading edge decreases the efficiency of the overall engine.